Safety razor blade



'Aug. 25, 1931.

R. E. THOMPSON 1,820,407

SAFETY RAZOR BLADE Filed Nov. 15, 1950 I vwwnkoz k L A. 110%]76011 33591115 flue/mu;

Patented Aug. 25, 1931 UNITED STATES RALPH E. THOMPSON, or BROOKLINE, MASSACHUSETTS, ASSIGNOR To Gram-rm SAFETY RAZOR COMPANY, OF BOSTON, MASMCHUSETTS, A CORPORATION 01' DELAWARE SAFETY nAzon BLADI Application filed November 15, 1930. SeriaiNo. 496,025.

This invention relates to Safety razors and relates more particularly to a blade for safety razors of the Gillette type.

An object of the invention is to provide a safety razor blade having a yielding edge.

'Another object of the invention is to provide a safety razor blade having vibratory shaving edges.

Another object of the invention is to separate the sharpened edges of a safety razor blade from other portions of the blade .which are subjected to softening heat treatment.

.While the rigidly positioned sharpened edges of safety razor blades have been entirely satisfactory tothe majority of safety razor users, others prefer blades having flexible sharpened edges which will yield to the skin and which will vibrate during the shaving operation. It is the purpose of the present invention to provide such a .blade for safety razors.

According to this invention the fleXlblG cutting edges are on narrow strips, almost completely severed by slots from the bodyportion, leaving the cutting edges very flexible and free to yield and vibrate.

In one embodiment of the invention, each ,flexible cutting edge is joined to the body portion of the blade. by a central narrow connecting neck portion, the cutting edge portions being separated from the body portion by slots on each side of the connecting neck portions.-

In another embodiment of the invention, the cuttingedges are mounted on narrow strips which are connected to the central I portion, by means of the narrow slot 8. The

blade is adapted to be mounted in the well known manner by means of the positioning body portion, one atone end of the blade and the other at the other end of the blade, and on the opposite side, with narrow slots separating the cutting edge portions from the central body portion except for the narrow connecting portions at the ends of the blade.

In still another embodimcnt'of the invention, the cutting edge portionsare substantially separated from the central body por-- tion by narrow slots, which extend almost to the end of the cutting'edges, the cutting edge portions, however, being connected around the slots to the body portion. The slots in this embodiment of the invention serve another useful function in that where it is desired to heat treat the central of the body of the blade to make it so ,so' as to increase its elasticlimit, the slots which substantiallyisolate the cutting edge portions from the body of the'blade, prevent the softening heat from reaching and affecting the tempered cutting edge rtions.

The invention will now ggexplained with reference to the drawings which illustrates the three embodiments of the invention above described:

Fig. 1 of the drawings. is aplan view of a safety razor blade, according to this invention, having the cutting edge portion Separated from the body portion except at a narrow central connectzng portion;

Fig. 2 is a; view of a safety razor blade, according to this invention, each ofthe cutting edge portions of which are attached to the body of the blade only by a single narrow end connecting portion, and

Fig. 3 is a view of a safety razor blade, according to this invention, having the cutting edge portions'separated from the body portion by narrow slots which extend almost to the ends of the blade.

- Referring now to Fig. 1 of the drawings, the blade there shown has a central body section 5 and the two flexible cutting edge portions 6. The cuttingedges 7 are formed on the outermost portions of the portions 6. The strips 6 are attached to the body 5 of the blade by means of the connecting neck portions 7, and are separated from the body portion '5, except for the narrow connecting when clamped in its holder, are adapted, as is well known, to have their upper portions contact with the edges of the cap member which bends the cutting edge portions down into their proper position relative to the edges rtion of a guard member of a holder. Since the cutting edge portions of the blade are flexible and free to vibrate, they will yield to the pressure of the skin during the shaving oper ation and will vibrate as the edge of the blade is drawn across the face.

The embodiment of the invention shown by Fig. 2 has the narrow strips 10, on which the cutting edges 11 are formed, joined to the central body portion 12 by the end connecting portions 13, each narrow strip forming the cutting edge portion, being attached to I the central body portion at only one end, and

it is preferred that the connecting portion 13 of one of the cutting edge strips be at the opposite end of the body portion of that of the other, as is clearly shown by Fig. 2. The blade is adapted to be positioned in its holder by means of the positioning apertures 14. \Yhen theblade is clamped in its holder, the cap portion, as has previously been explained. contacts with the cutting edge portion ]l1sl back of the cutting edge, and positions the cutting edge in its proper relation to the guard member of the holder. Since each cutting edge portion is free to vibrate, except at one of its ends, the. cutting edge portion will yield to the pressure of the flesh in shaving and is free to vibrate.

The embodiment of the invention shown by Fig. 3 consists of the blade having the central body portion 15, the cutting edge portion 16. and the narrow slots 17 which are placed between the cutting edge portions 16 and the central body portion. The cutting edge portions are connected to the central body portions by means of the narrow connecting portions at each end of the slot 17 so that the cutting edge portions are but little restrained in their movement by the central body portions, so that the cutting edge portions are free to yield to the flesh in shaving and to vibrate.

The structure shown by Fig. 3 has another advantage in that the central body portion may be softened by heat treatment without the heatreaching the tempered cutting edge portions. It may be desirable to soften the central portion of a safety razor blade. as

indicated by the shaded lines of Fig. 3. This softening is accomplished after the blade is tempered by heating the shaded portions. The purpose of the softening is to increase the elastic limit of the metal so that the strains which occur in the bending of the blade, while being clamped in its holder, may be easily absorbed by the softened portions where the bending of the blade occurs.

lVhereas one or more embodiments of the invention have been described for the purpose of illustration, it should be understood that the invention is not limited to the exact details described, as many departures may be made by those skilled in the art Without departing from the spirit of the invention.

\Vhat is claimed is: 1. A safety razor blade having a sharpened edge portion and a body portion. said sharpened edge portion being attached to said body portion by a narrow centrally placed neck and being separated from said body portion on each sitleo'f said neck by longitudinal slots located between the sharpened edge'and the center of the blade.

:2. A safety razor blade having opposed longitudinal sharpened edge portions and a central body portion, said sharpened edge portions being attached to said body portion by a narrow centrally placed neck and being separated from said body portion on each side of said neck by longitudinal slots located between the sharpened edge and the center of the blade.

3. A safety razor blade having a sharpened edge portion and a body portion. said sharpened edge portion being attached to said body portion by a narrow neck at one end of said edge portion. the remainder of said edge portion being spaced from said body portion by a longitudinal slot.

4. A safety razor blade having opposed longitudinal cutting edges and a body portion. said cutting edge portions being attached to said body portion each by means of a narrow neck at one end and being spaced from said body portion along the remainder of the cutting edge portions, and being separated from said body portion by longitudinal slots.

A safety razor blade having a longitudinal sharpened edge portion and a longer body portion, the body portion being separated from the cutting edge portion by means of a longitudinal open-ended slot extending substantially as long as the cutting edge.

6. A safety razor blade having opposed longitudinal cutting edges and a central body portion longer than said cutting edge portions, each of said cutting edge portions being separated from said body portion by means of a longitudinal open-ended slot substantially as long as its cutting edge.

7. A safety razor blade having opposed longitudinal cutting edges and a central. body portion longer than said cutting edge portions, each of said cutting edge portions being separated from said body portion by means of a longitudinal open-ended slot substantially as long as its cutting edge. the central bodv portion being heat treated, the slot preventing the heat from affecting the temper of the cutting edges.

Signed at Boston, Massachusetts,-this 14th day of November. 1930.

' RALPH E. THOMPSON. 

